Use Sync FakeServer in Android tests via custom APK

chrome/test/android/javatests/src/org/chromium/chrome/test/util/browser/sync/SyncTestUtil.java

Index: chrome/test/android/javatests/src/org/chromium/chrome/test/util/browser/sync/SyncTestUtil.java
diff --git a/chrome/test/android/javatests/src/org/chromium/chrome/test/util/browser/sync/SyncTestUtil.java b/chrome/test/android/javatests/src/org/chromium/chrome/test/util/browser/sync/SyncTestUtil.java
index d525a4ff59ee19df2bc55a6fe974f0b60319e1c1..1735cdd6c36a66bee004f41a47f52c4804518030 100644
--- a/chrome/test/android/javatests/src/org/chromium/chrome/test/util/browser/sync/SyncTestUtil.java
+++ b/chrome/test/android/javatests/src/org/chromium/chrome/test/util/browser/sync/SyncTestUtil.java
@@ -23,6 +23,7 @@ import org.chromium.content.browser.test.util.CriteriaHelper;
 import org.chromium.sync.signin.AccountManagerHelper;
 import org.chromium.sync.signin.ChromeSigninController;
 import org.chromium.sync.test.util.AccountHolder;
+import org.chromium.sync.test.util.FakeServerHelper;
 import org.chromium.sync.test.util.MockAccountManager;
 import org.json.JSONArray;
 import org.json.JSONException;
@@ -62,6 +63,10 @@ public final class SyncTestUtil {
     // Native switch - chrome_switches::kSyncServiceURL
     private static final String SYNC_URL = "sync-url";
 
+    // Pointer value for the FakeServer. This pointer is not owned by native
+    // code, so it must be stored here for future deletion.
+    private static long sNativeFakeServer = 0L;
+
     private SyncTestUtil() {
     }
 
@@ -392,4 +397,42 @@ public final class SyncTestUtil {
             return super.getSystemService(name);
         }
     }
+
+    /**
+     * Creates and configures FakeServer.
+     *
+     * Each call to this method should be accompanied by a later call to deleteFakeServer to avoid
+     * a memory leak.
+     */
+    public static void useFakeServer(final Context context) {
+        if (sNativeFakeServer != 0L) {
+            throw new IllegalStateException(
+                    "deleteFakeServer must be called before calling useFakeServer again.");
+        }
+
+        sNativeFakeServer = ThreadUtils.runOnUiThreadBlockingNoException(new Callable<Long>() {
+            @Override
+            public Long call() {
+                FakeServerHelper fakeServerHelper = FakeServerHelper.get();
+                long nativeFakeServer = fakeServerHelper.createFakeServer();
+                long resources = fakeServerHelper.createNetworkResources(nativeFakeServer);
+                ProfileSyncService.get(context).overrideNetworkResourcesForTest(resources);
+
+                return nativeFakeServer;
+            }
+        });
+    }
+
+    /**
+     * Deletes the existing FakeServer.
+     */
+    public static void deleteFakeServer() {
+        if (sNativeFakeServer == 0L) {
+            throw new IllegalStateException(
+                    "useFakeServer must be called before calling deleteFakeServer.");
+        }
+
+        FakeServerHelper.get().deleteFakeServer(sNativeFakeServer);
+        sNativeFakeServer = 0L;
+    }
 }